Fault clearance procedures, Dsp failure, Card failure – Nortel Networks NN43001-563 User Manual

Page 419

Advertising
background image

Fault clearance procedures

419

Fault clearance procedures

This section provides possible solutions to such faults as the following:

DSP failure

card failure

DCH failure

DCH link failure

PC Card failure

DCHIP card failure

power loss

DSP failure

If one of the DSPs does not respond, a DSP reset is automatically initiated
by the host and an dspResetAttempted alarm is raised. If the DSP fails to
recover after the reset, a dspResetFailed alarm is raised and that DSP is
marked as unusable. Any channels associated with that DSP cease to
respond to the system and are ultimately taken out of service by the system
background audit procedures.

If a DSP fails, the following can occur:

A DSP fails when no channel on it is in use (that is, no existing call
uses that DSP). All channels associated with that DSP are marked as
DISabled until the DSP recovers. The leader card is notified so that no
incoming call is assigned to those channels.

A DSP fails when at least one of its channels is in use. All calls
associated with that DSP are dropped and all its channels are put into
the DISabled state. The leader card is notified so that no incoming call
is assigned to those channels.

When the system initiates a call at a channel of a failed DSP, the DCHIP
card sends a "RELease COMplete" message in response to indicate that the
channel cannot be used. Then, the system generates the alarm "PRI0101"
and locks out the trunk by marking it "BUSY". This mechanism is also used
to lock out a channel that does not have a corresponding DSP port.

When the DSP recovers, all the associated channels are put into the "IDLE"
state. "REStart" messages for all channels are sent to the system to reset
the trunks to the "IDLE" state. The leader card is informed and incoming
calls can be assigned to those channels.

Card failure

Following a reboot, if the IP trunk card displays a code in the form of F:xx on
the faceplate Maintenance display, this indicates an unrecoverable hardware
failure. The card does not register with the system.

Nortel Communication Server 1000

IP Trunk Fundamentals

NN43001-563

01.01

Standard

Release 5.0

30 May 2007

Copyright © 2007, Nortel Networks

.

Advertising